Add initial files
Add tox configuration
Add manifest input for readme
Add Travis CI configuration
Only remove standard modules by default

Other modules may cause side effects on import.
Make test compatible with Python 2.7
Only delete safe modules
Add example
Close temporary file
Handle case where import is indented
Only return unused
Fix typo
Remove duplicate import
Rename function
Add unit test
Use multiple passes of pyflakes
Add more complex test case
Add more unit tests
Add complete test coverage
Make tests work on Python 2.7